The goal of this project is to evaluate the chronic toxicity and carcinogenicity of 2-hydroxy-4-methoxybenzophenone (HMB), following dietary exposures. HMB is used in sunscreens. 2-Year chronic toxicity and carcinogenicity studies of HMB are in the in life phase. These studies include perinatal exposures (exposure during gestation and lactation). Humans are likely to be similarly exposed to these compounds through the environment. Perinatal exposure occurs during critical periods of development and can result in differences in toxicity/carcinogenicity as compared to exposure starting only from adulthood. In the HMB study, rats were exposed perinatally prior to the 2-year study, while standard studies are being conducted in mice. Keywords: toxicity, carcinogenicity, diet, perinatal, 2-hydroxy-4-methoxybenzophenone